Muscle weakness, fatigue, and torque variability: effects of age and mobility status.
Muscle Nerve
; 49(2): 209-17, 2014 Feb.
Article
em En
| MEDLINE
| ID: mdl-23674266
INTRODUCTION: Whereas deficits in muscle function, particularly power production, develop in old age and are risk factors for mobility impairment, a complete understanding of muscle fatigue during dynamic contractions is lacking. We tested hypotheses related to torque-producing capacity, fatigue resistance, and variability of torque production during repeated maximal contractions in healthy older, mobility-impaired older, and young women. METHODS: Knee extensor fatigue (decline in torque) was measured during 4 min of dynamic contractions. Torque variability was characterized using a novel 4-component logistic regression model. RESULTS: Young women produced more torque at baseline and during the protocol than older women (P < 0.001). Although fatigue did not differ between groups (P = 0.53), torque variability differed by group (P = 0.022) and was greater in older impaired compared with young women (P = 0.010). CONCLUSIONS: These results suggest that increased torque variability may combine with baseline muscle weakness to limit function, particularly in older adults with mobility impairments.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Envelhecimento
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Fadiga Muscular
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Debilidade Muscular
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Torque
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Limitação da Mobilidade
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Contração Muscular
Tipo de estudo:
Diagnostic_studies
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Prognostic_studies
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Risk_factors_studies
Limite:
Adult
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Aged
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Aged80
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Female
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Humans
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article